Gyroscopic device



Filed July 3l, 1925 3 Sheets-Sheet 1 ll Hl Jan' 4 192? T. UMETsU GYROSCOPIC DEVICE Filed July 3l. 1925 3 Sheets-#Sheet l2 @VMM Jan. 4,1927

T. UM TSU GYRSGOPIC DEVICE Filed July 5l, 1925 3 SheetS-Sheet 3 lzvvenfor:

` y Ri/wzl' Mmm@ lll patented dan.' 4l,- i927,

TADAYOSHI UMETSU, F SAIHAlU-GUN, JAPAN.

GYROSCOPIC DEVCE.

T his invention relates to a gyroscopic device for establishing a .fixed horizontal plane on a moving body, ormore precisely to a gyroscopic device for holding an instrument or other device on a moving body, such as a ship or an aircraft, at a iixed angular relation to a vhorizontal plane.

According to t-his invention a true horizontal plane formed by a heavy liquid Such as mercury contained in an open vessel, which is suspended so'as to be freely rotatable around three axes, is taken as a stand ard of reference, and the slightest deviation of the axis of the gyroscope from the hori- P zontal position is made to cause controlling means to operate in one or the other direction, calling forth a force acting to suppress such deviation. This force, which counteracts said deviation of the gyroscope, causes the wheel to precess in a horizontal plane, which motion, When opposed in the horizontal Plane, will in turn call forth a pre cession in the vertical plane, driving the lyroscope in the saine direction as it would have been driven by the direct action of the controlling means. ln consequence of this precession in the vertical plane, the iirst named deviation will be totally suppressed, and the wheel will shoot over the position of `equilibrium, and thus will cause the controlling means to operate in the opposite direction. ln this wisc. the gyroscope will swing within the limits of a small prea determined range in the vertical and horizontal planes, holding itself in 'a true horin zontal direction in lthe practical sense of the Word. i 4

l/Vhen a {lyre-wheel possessing freedom of movement about three axes is controlled, as in this invention, by the aid of means actin to suppress any deviation of the axis ed rotation ofthe gyrocope from the horizontal position,l the device will behave in one of the following manners according to the circumstances (a) "When a couple is applied to the Wheel in a vertical plane, it will precess in the horizontal plane and the motion will have no direct eii'ect upon the controlling' means.

(7)) Rotation of the earth around its own axis or the change of latitude due to the change of position of the ship or the aircraft will have an effect of causing the rotating gym-wheel to incline with respect to a horizontal plane which varies from instant to instant. 'llie tilt of the Wheel caused thereby will call the controlling' means into play, making` the Wheel process in a liori` zontal plane.`

(c) W'hen a couple is applied to the wheel in a horizontal plane, a precession is called forth to taire place in a vertical plane, cans ing the controlling means to exert a force to oppose the resulting vertical movement, and in this cage also a procession in a horizontal plane results.

lln'eaeh of these instances, the disturbances to which thegyroscope is subjected are finally reduced to a horizontal preeessional motion, which when opposed or controlled will again lead to a precession in a vertical plane which takes place in such a direction that it would have resulted directly from the finit applied force. rlhat is to say, in

the first case above mentioned, the gyro- "Ill scope will become inclined and subjected to the action of the controlling means, ln the second case, after it has assumed the horizent-al direction momentarily, it will shoot over to the opposite side, to be again acted upon by the controlling means in the opposite direction. lin the third ease, a precesA sion in the oppo'ite direction in the horizontal plane `will result.

rl1 o sun'imarize, the behavior of the device according to this invention, when disturbed and when properly restricted in its horizona tal motion, Will be a swing in one direction in a vertical planethcn in one direction in a horizontal plane. then in the opposite direction in the vertical plane, and then in the opposite direction in the horizontal plane, the swings in the horizontal and ver; tical planes taking place in an alternate manner. TWhen the amplitudes of the oscillation are restricted, rzhorizontally and vertically, to narrow limits', the axis of the gyrolcope will remain practically horizon-- tal, ,and the parte attached thereto will assume a position which has aconstant anv `eular relation with respect to a horizontal plane.,

The gyroscopic device accordinrg to this invention, as above described, enables a body to be held at a tired angular position with respect to a horizontal plane, lf two of such devices are provided, it will be possible 'lo form a table of reference upon a moving body, such as a ship or an aircraft. which will be sufficiently firm to support an instrumeiit or some other object of 'a coinparaiively light Weight. and will provide for various applications in the devices which require a horizontal plane as a plane of reference in their operation. For exam le, a set of two gyroscopic devices dispose in perpendicular relation to each other may be connected, by means ot an electrical controlling device ot a suitable type, to a platform which is properly geared to the deck,

tionoit a ship or an air-craft, on which theapparatusjis mounted. 1n the said drawing: l

Figure lis a front view, partly in section, of one form ot the gyroscopic device according to 'my invention.

Figure 2 is a front view, partly in section and partly broken away, of the control magnets, switch bars andthe mercury level.

Figure 3 is a plan view of saine.

Figure 4 is a plan view ot the apparatus fiom which the gyrowheel and all the parts connected therewith have Ibeen removed, showing the outer casing, gimbal rings and annular mercury trough only.

Figure 5 is aV plan view ot the foundation disc.

Figure 6 is a). side view of said disc, together with the annular float connected thereto. y

Figure 'i' is a front view of the top part of the main vertical shaft with a supporting board pivotally mounted thereon.

fia'

Figure 8 is a side view of Figure 'i'. i

Referring more particularly to the numerals of reference on the cran/ing, 1 is an `annular mercury trough pivotally suspended trom the ring 2 by means ot journals 8, 3. The ring 2 is pivotally suspended from the ring 4l by means of journals 5, 5. rlhe ring Il is in turn suspended from the outer l springs 7. The journals', 3

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casing @by means of a number ot spiral and 5, 5 are situated mutually at right angles to each other. Vln this manner the mercury trough is practicallyr tree trom rolling and pitchingv thereto by the radial portions 13 leaving therebetween openings 14. The float 8 is provided at the bottoni thereof with resilient springs 15 to further dampen vibrations.

The gym-wheel together' with all its dependent parts mounted upon the rvertical main shaft 16 are arranged to rotatably rest upon the foundation disc 1() by means of the ball bearing 17 provided between the -said disc and the flange 18 rigidly secured to the shaft 16.

The main vertical 4shat't 16 which is rotatable together with the flange 18 relative .to the foundation disc 10 is provided, aty the upper end thereof, with a pair olf laterally extending' horizontal bars 19, 19, the lower portion of the said shalt extending downwardly through the disc 10, and being biturcated to form a ring 2() to pivotally support the gyroscope casing 2l`at trunnions 22. At the top of the shaft 16 is provided a knife edge 23, upon which is pivotally mounteda horizontal supporting board 24,

will rotate together with the main shat't 16 about the vertical axis. The gyroscope consists ot the rotor element of a threephase induction motor, the stator being fixed inside the casing 21, and is operated by three so that the board 2st is rotatable in the plane including the axis 25 of the 4gyroscope but ino gearing with the worm 30 which is provided on the operating handle 31.

The supporting board 24, with the part mounted thereon, would be freely rotatable, in a vertical plane, on theknife-edge 23, if it had not been constrained to move in unison with the ygyroscope by means of the verticalv connectingrod 32 -pivoted at one end to the supporting board and at the other end to a projection 33 provided on the gyroscope casing lying on the axial line 25. .By this means the supporting board 2d and the axis of the gyroscope are con necte'd so as to be in parallel relation all the time, the oscillating motion ot the supporting board 24 in a vertical plane being guided by projection 34. attached to the rear wall of the knife edge 23 and extending clear up to the downwardly projecting lug 35 provided on the rear Wall of the supporting board. and a pair ot adjusting screws 36 provided at each end ot the horizontal bars 19, adjusted so as to nearlv touch with the depending arcuate extensions 3T provided iin iso

,pended, by means ota rods 38 securely attached thereto, a control Aboard 39, soxthat this board 39 will always inove in parallel relation with the supporting board 24 and consequently with the axis of the gyroscope. Un the control board 394 are provided electromagnet-s 40, 43 cooperating with the adjacently situated electro,- niagnets 41, 42 securely mounted on the verticel shaft 1G. g ARigiclly mounted upon the ange 18, which is rotatable upon the foundation disc l0, is a mercury level 44 consisting ot a lllshaped vessel filled with mercury.. lin the lli the knite edges 48 49 vert-ical leg'portions "of this mercury level are arranged cylindrical floats 45, 45.

ln the spacebetween the control hoard 39 and the ncrcury level 44 are provided a'pair of switch hars 46. 47 pivot-ally mounted upon provided upon the top ends of the cylindrical floats 45, 45. Each of these switch bars consists of a long liori'n j/,ontal portion and a short vertical portion.

rlhe long, horizontal portions extend right up to the opposite end ot the mercury level and are i'orrned with contact points 50, 5l respectively to come into contact with the extensions 52, 53 made on the leg portions ol the mercury level, while the short vertical portions extend half Way up toward the controhltoard und are provided with adjustable contact points 54, 55 respectively to cooperate with the contact pieces 56, 5l pro vided at the ends of the controllooard 39. The distribution of weight in 'each ot the switch liars 46, 47 with respect to the re spective points ot suspension is such thut the long;l horizontal port-ions overbulancethe short vertical portions.

The electroniagnets 40 and 4l, being in se ries. areconnccted on the one hund, through the line 58, to one of the switch laars 46, und

on the other hand'` through line 59, to one v side oiiithe source of electricity.- ln the same wey. the electromagnets 42 and 43, being in series, are connected on the one hand, through Sil the line 60, to the other switch loar 47, vund on the other hand, through the line 59, to the sarne side ol the's'ource ot current. Ilihe lll-shaped mercury level 44 is connected to the other side ot the source of current through the line 6l.

The contact pieces 56 and 5'? are suitably insulated from the control hoard 39, the knifeedges 48 and 49 are insulated trom the floats 45. 45, and the mercury level 44 is insulated trom the flange 18.

llhen the Contact point at the end of the horizontal portion of one of the switch bars, soy 4T. makes 'contact with the extension 59; provided yat the upper edgeof the mercury level, the electrical lcircuit oil the electromag- 'together and in cor nets 42 und 43 will close through the line 61 leading troni one side et the source ot electricity to the mercury levelL 44 to the extension 52 ut the left end. oit the level, then to the switch bar 47 through the Contact 50, the .line 60, the electromagnets 42, 43, und then hack to the source ont supply through the line 59. ln this rnanner the electromagnets 42 und 43 will he 'energized and will exert a torce ou the control board und conse quently'the unis or the gyroscope..

When the control hoard 39, which moves parallel with 'the axis ot the gyroscope, lies horizontal, the switch here 46 and 47 will .he pressed loy the contuct pieces 56 and 5? at the contact points 54, '55 provided et the vertical portions oitthe switch hers, .and the other ends 50 und. 5l will he ruised tree troni Contact with the en tensions 52 and 53 provided ut the upper edges ot the mercury level. lin this case the circuit ot the electroinugnets at either eide ot the vertical shaft lli is lorolren, andthe controlling;a means will not operate et ull.

lt, however, hy any reason whatsoever, the unis ol the gyroscope und consequently the control hoerd39 loeconie inclined with respect to u. horizontal plone, one ol the pairs o4 electroniagnets will he celled into .play to erm-t en opposing torce 'to euch deviation o? the. gyroscope. To taire a concrete example, let us suppose tht-it the control llllll liourd'has lie-:orne inclined in such e inani ner that right hend end has risen uudz the lett hund end descended, au shown Sonie- Xvhat eitaggeretetl in 'ure Consequently, the lett switch har .in hecoines depressed et the Contact ioint 54 and the contuct 5l lil@ rises and heconresdetached from the erru 4tensirni lill.. ulli'ethe riu'ht switch liar 4l,

vwill tall ley its ovv/'u horizontal plone, and the whole movable System including' the gi'y'roscope, verticul shaft l5 and the parts attached thereto,will,A rotate upon the hearingl'i'. l

'lhis rotation around the verticaal unis, however, will lee limited luy' the observer operating the huudle 3l or l'iy uny other suitube inechunicul ineens, whereby the oppos`- ing-horizontal torce will hccnet-ted. Jfllns horizontal force will cull torth epreceu sional4 motion in u vertical plane and the gvroscope will he driven in such a direction as it' it had directly tronuigrncts 42, 43. 'the unis ot tliegrvro scope will thus swing in the vertical plane und will eventuully pues overthe horiuontal gyroscope to oppose itslieen driven by the e`ec-m 'titl position and shoot over to the opposite side, to be acted upon by the other pair ot electromagnets 40, 41, producing in turn a horizontal precessional motion in the opposite direction. l

ln this manner, the supporting board 24C, which is connected with the gyrosoope by means ot the rertical rod 32, together Wit the parts mounted on the said supporting hoard. will swingr successively around a horizontal and then the vertical axes.,

The horizontal distances ot' the Contact points al, ot the switch bars from the respective pivotal points 4 8, ai) being small compared to those ol the contact points 50, 51, the, slightest deviation of the gyroscopic axis from the horizontal direction is suflicient to call the controlling means into play. 'l`herefore the vibration of the supporting board 2l which takes place all thc time is hardly7 perceptible and it may very well be considered from a practical point ot view that the supporting board al ays lies in a horizontal plane.

lf it is desired to rotate the telescope in azimuth, it is necessary simply to apply torce.r say at the operating handle 31, in the direction in which the apparatus should turn. Then this torce applied in a horizon tal plane Will produce a prccessional motion in a vertical piane; which when opposed by the electrodynamic controlling means, will again be transformed into a precession in the horizontal plane. rThis takes place invithe same direction as the first applied torcer so that it will appear as though it had directly been caused by the torce applied at the handle Ell.

'lhe rotor ot' the three phase induction motor should of course be balanced as far as possible to minimize the vibrations. The conibination of the mercury` trough in cooperation with the resilient springs provided on the bottom of the annular float., and the inner and outer rings pivoted at the trunnions situated at mutually right angles, all ot' these together being connected by 'the spiral springs with the external casing, will serve to prevent they transmission ot the slightest disturbance taking; place outside the device. 'llieretore the surface ot the mercurv in the lll-shaped vessel will maintain a. tiue horizontal plane.. Also the Whole moving system being assembled in such a manner that the centre of gravity lies sufficientlji1 below the float in the annular trough, the vertical'n'iain shaft will remain normally in an upright position.

ldrhen thehead ot the ship turnsg the turnin cl will simply cause a rotation ot the system around the Vertical shaft 'lti at the bearu ingr 1T. ,X horizontal couple resultinff trom a slight t'riction at the bearinpr will lead to a procession in a rertical plane and Willcause series o I` oscillating motions in the limits {inal motion' prescribed by the clearance provided on the switch bars; exactly in the manner described above. In this case, the vertical connecting bar 32 passing through the foundation disc 10 will travel in the space 14 between the radial portions 13. lt the turning ot the ship be so ,Qfreat that the system cannot be turned on the disc because of the existence ot the radial portions 13, the foundation disc l0 itselt can be turned in the mercury trough 1.

In the drawing and in the above description, I have shown tivo pairs ot electromagnets as the means to exert a force to suppress tilt of the gyroscope, but they can be replaced by any suitable means, such as an electric motor properly connected to the casing ot the ffyroivheel at one of the trun'nions 22 which is in perpendicular relation to the direction ot the axis'2 ot' the wheel so that it will exert an opposing turning moment when the wheel becomes inclined to the horizontal direction. Also it is evident that U- shaped level can be provided separately from the device.

l claim:

1. A device for holding a body at a fixed angular position With respect to the horizontal, comprising a vertical shaft; a gyroscope carried thereby; a control board connected to the gyroscope casing to tilt with the same; electrical means for setting up forces to resist tilting of the gyroscope axis in ditterent directions about a horizontal axis; a supporting member carried by said shaft;

' and a plurality ot switches embodying switch bars ulcrumed on said member and directly operated by the control board to open or .close the circuit of Said electrical means.

2. fbdevice for holding a body at a fixed angular position with respect to the horizontal, comprising a vertical shaft; a gi'yroscope carried thereby; Aa control board connected to the gyroseope casing to tilt with the same; a group ot magnets attached to said shaft and a group ot companion magnets carried by thecontrol board for setting up forces to resist tilting ot the gyroscope axis in ditterent directionsabout a horizontal axis; a plurality ot switches: and conductors extending between the magnets and switches, said switches beineoperated by the control board to open or close the circuit ot' the magnets.

3. A device for holding a body at a lixed angular position with respect to the horizon tal, comprising a vertical shaft; a gyroscope carried thereby; a control board connected tothe gyroscope casing to tilt with the same; a group ot magnets attached to said shaft and a group ot companion 'magnets carried bythe control board for setting up forces to resist tilting ot the gyroscope axis in different directions about a horizontal axis; a supporting member carried by said shaft; a

plurality of switches embodying Switch hars i'nlcrnmed on said member; and conductors extending between the magnets and the switch bars. said bars being' directly operated by the control board to open or close the circuit of the magnets.

4. A device for holding a body at a fixed angular position with respect to the horizontal, comprising a gyroscope, a controlling vboard connected to the gyroscope casing. a

mercury level. a oat in said level, a switch bar fulcrumed on the said float and playing in the space between the said level and controllinglioard, and electrical means to produce force to suppress any tilt of the axis of the gyroscope with reference to a horizontal axis, the said switch-har closing or opening the circuit of said electrical means.

5. A device for holding.,Y a body at a fixed angular position with respect to the horizontal, comprising a gyroscope, aV controllinzl;-

TADAYOSHI U'METSU. 

